Pharmacokinetics Flashcards
Name the different drug forms (13)
- Aqueous preparation
- Alcoholic preparations
- Solid/ Semisolid preparation
- Powder
- Tablets
- Troches and Lozenges
- Capsules
- Delayed release products
- Enteric coated products
- Suppositories
- Ointments
- Transdermal products
- Parenteral injections
Name some routes of administration and it’s time of onset (I) (4pts) (15-60mins)
Rectal- 15-30 minutes
Vaginal- 15-30 minutes
Oral - 30-60 minutes
Transdermal- 30-60 minutes
Name some drug routes of administration 2 (5pts)
Sublingual- several minutes
Buccal- several minutes
Subcutaneous - several minutes
Intramuscular- several minutes
Intratecal- several minutes
Name some routes of drug administration (III) (3pts)
Intravenous- within 1 minute
Intraarterial- within 1 minute
Inhalation- within 1 minute
What are the indications for oral route medications
It is the safest and most convenient route, when possible
What are the indications for sublingual drugs?
When rapid effects are needed
What are the indications for Buccal drugs?
It is a convenient dosage form for most drugs
What are the indications for rectal drugs?
Used when patient cannot take oral drugs, when parenteral is not indicated, used for local effects
What are the indications for trans dermal drugs?
Convenient dosage form that provides continuous absorption, and systemic effects over many hours
What are the indications for subcutaneous drugs?
Used for drugs that are inactivated by the G.I. tract
What are the indications for intramuscular drugs?
Used for drugs that have poor absorption, used when high blood levels are required, used when rapid effects are desired
What are indications for intravenous drugs?
Used an emergency situations where immediate effects are required, used when medication is administered by infusion
What are the indications for intra-arterial drugs?
Used for local effects within an internal organ
What are the indications for intrathecal drugs?
Use for local effects within the spinal cord
What are the indications for drugs administered by inhalation?
For locally effects within the respiratory tract?
What are the indications for medication administered topically?
For local effects on the skin, eye and ear
What are the indications for medication administered vaginally
Local effects within the organ
Name the pharmacokinetic phases
Absorption
Distribution
Metabolism
Excretion
Describe absorption in the pharmacokinetic phase
- This involves transport mechanisms example filtration, and active and passive transport
- Absorption is determined by lipid solubility, drug ionization, and drug formulation
Describe distribution in the pharmacokinetic phase
It involves plasma protein binding
Level of blood flow
Ability to cross the blood brain barrier
Describe metabolism in the pharmacokinetic phase
Involves the drug microsomal metabolizing system where enzymes in the liver metabolize (break down) foreign substances
Describe excretion in the pharmacokinetic phase
Involves the following systems:
Renal
Gastrointestinal
Respiratory
Also, involves sweat, saliva, lactation
What are the clinical factors that determine drug intensity and response?
Half life
Blood drug levels
Bioavailability
Describe a half life in terms of the intensity of drug response
The time it takes for blood concentration to drop to half its original level
Describe blood drug levels in terms of the intensity of drug response
The intensity of a drug is determined by the concentration of drug in the blood
Describe bioavailability in terms of the intensity of drug response
This is the percentage of drug absorbed into the bloodstream
What are the factors of individual variation? (8pts)
- Age
- Weight
- Sex and percent body fat
- Genetic variation
- Emotional state
- Placebo effect
- Disease state
- Patient compliance
What are the pharmacokinetic considerations for pediatrics?
-Drugs taken by the mother can pass to the fetus
- drugs can pass through breastmilk to infants
- pharmacodynamic and pharmacokinetic are different in pediatric and adult patients
How does pharmacodynamic and pharmacokinetic differ in the adult versus pediatric patients?
- drug absorption differs
Infants have small, skeletal muscle mass and have limited movement - distribution of drugs differ
Infants have a higher percentage of body water, lower percentage of body fat - drug metabolization and excretion is slower in infants
Name the FDA pregnancy categories
A
B
C
D
NR
Describe the FDA pregnancy category A.
A- studies in pregnant woman have not yet shown risk to the fetus
What is incompatibility?
Usually refers to physical altercations of drugs, before administration, when different drugs are mixed in the same syringe or other container
What are additive effects?
- When the combined effect of two drugs, is equal to the sum of each individual effect
- These drugs produce the same biological response and use the same mechanism of action
What is summation?
When the combined effect of two drugs, is equal to the sum of each individual effect
- These drugs produce the same biological response but use a different mechanism of action
What is synergism?
When the combined effects of two drugs is more than the sum of each individual effect
What is antagonism?
When the combined effects of two drugs is less than the sum of each individual effect
What is tolerance?
This is decreased drug effect with repeated administration
Name two types of tolerance?
Metabolic tolerance
Pharmacodynamic tolerance
What is dependence?
- Where reliance on the drug becomes a vital to the well-being of the patient
- can have a physical or psychological impact
- leads to addiction action
Describe the FDA pregnancy category B.
B- drug studies have not been performed in pregnant women; animal studies has shown no fetal risk
Describe the FDA pregnancy category C.
C- Drug studies have not been performed in pregnant women or in animals, or animal studies have revealed some teratogenic potential but the risk to the fetus is unknown
Describe the FDA pregnancy category D.
D- Drug studies have revealed adverse risk to the fetus. The benefit-to-risk ratio of the drug must be established before use during pregnancy
Describe the FDA pregnancy category E.
E- drug studies reveal teratogenic risk in women and/or animals; risk clearly outweighs the benefit. Drug is contraindicated in pregnancy
Describe the FDA pregnancy category NR.
NR- drug has not yet been rated by the FDA
What is pharmacodynamic tolerance?
High concentrations of a substance constantly binding with the receptor, desensitizing it through constant interaction
What is metabolic tolerance?
Metabolic tolerance occurs when the body becomes more efficient at eliminating the drug or alcohol as it is being used
